section 6 lightning
ground ring electrode
A conductor that encircles a structure that is in direct contact with the earth is called a___?
voltage protection rating (VPR)
A rating (or ratings) selected by the manufacturer based on the measured limiting voltage determined when the SPD is subjected to a combination waveform with an open circuit voltage of five kilovolts and a short circuit current of three kiloamperes is called a_____?
strike termination device
A_____is a component of a lightning protection system that intercepts lightning strikes and connects them to a path to ground.
100'
All structures require at least two down conductors and at least one additional down conductor for every____ of roof perimeter over 250 feet.
3/16"
Electrically continuous structural steel may be used as a strike termination device or main lightning protection conductor if it is at least_____thick.
60'
For structures exceeding_____in height, the interconnection of the lightning protection system grounding electrodes and other grounded media must be in the form of a ground loop conductor.
loop conductor main lightning conductor
_____ are used to interconnect lighting protection systems down conductors, grounding electrodes, or other grounded media. these must not be smaller than the size required for the _____.
loop conductors
_____are used to interconnect lightning protection system down conductors, grounding electrodes, or other grounded media. These must not be smaller than the size required for the main lightning conductor.
lightning both upper and lower extremeties
_____conductors and all other lightning protection components concealed in steel reinforced concrete must be connected to the reinforcing steel at_____.
loop conductor
a conductor that encircles and which interconnects ground electrodes is called a
.032" 2 square feet
a ground plate must have a minimum thickness of_____ and i minimum surface area of_____.
20
in reinforced concrete structures, where reinforcement is interconnected and grounded to the lightning protection system, the lighning protection system down conductors and other grounded media must be interconnected with a loop conductor at intermediate levels not exceeding_____.
1/8" 1/4"
roofs having a span of 40' or less and a pitch of_____or greater, and roofs having a span of more than 40' and a pitch of_____or greater are considered to be pitched.
pvc
running down conductors in_____and other nonmetallic case eliminates the need to make bonding connections to the down conductors.
-direct connection -the use of individual conductors routed through the roof or parapet walls to the structural steel framework -the use of an external lightning conductor
strike termination devices must be connected to the structural steel framing by_____, or by _____, or by _____ that interconnects all strike termination devices.
40 20
surge protective devices installed at the service entrance must have a minimum (Imax) rating of_____KA 8/20 per phase or a nominal discharge current (In) rating of_____Ka 8/20 per phase.
cleaned to bare steel free of any contaminates
Prior to making an exothermic connection to steel, the surface must be___ and ___
true
The use of the word "shall" indicates a mandatory requirement.
metal clad structure
a structure that has sides or a roof covered with metal is called_____.
electrical metal framed structure
a structure with electrically continuous structural members of sufficient size to provide an _____path that is equivalent to lightning conductors is called_____.
surge arrestor
a_____is a protective device for limiting surge voltages by discharging or bypassing surge current
60' inherently bonded
grounded and ungrounded metal bodies exceeding_____in vertical length must be bonded through structural steel members as near as is practical to their extremities unless_____through construction at these locations.
100'
horizontal lightning conductor runs must be connected to the reinforcing steel at intervals not exceeding _____.
nominal discharge current (In)
the peak value of 8/20 ms current wave form selected by the manufacture for which an SPD remains functional after 15 surges
permanently
the surge protection requirements outlines in NFPA 780 include only_____installed SPD's.
10"
the tip of air terminals must be at least_____above the object or area it is to protect.
maximum discharge current (Imax)
this is the maximum instantaneous valve of the current through the SPD having an 8/20 ms waveform.
labeled AHJ
when a product is_____, it means there is some sort of symbol or identifying mark from an organization that is acceptable to the _____.
8 square inches
when structural steel is utilized as the down conductor the bonding plate must have at least _____of bonding surface.
18"
when topsoil is less than_____,concrete encased electrodes, ground ring electrodes, ground plate electrodes, or any combination of there of are to be used.
8' 10'
where ground rods are used for grounding electrodes, they must be in contact with the earth for a minimum of_____and extend to a depth of not less than_____ below finished grade, except as permitted by the requirements for shallow soil.
20'
air terminals less than 24" tall must be placed on the ridges of pitched roofs and around the perimeters of flat or gently sloped roofs at intervals not exceeding_____.
18"
bimetallic connectors cannot be used within_____of the earths surface.
75' larger or heavier
class 2 materials are used on structures that exceed______in height. they are generally _____ than class 1 materials.
commercial electric work 95% conductive
copper materials are made from the same grade of copper ones used for_____; these are generally designed to be_____ when annealed.
50' 50'
flat or gently sloping roofs that exceed_____feet in width or length must have additional strike termination devices located at intervals not to exceed_____on the flat or gently sloping areas.
